Allow disabling colors (#118)

* Allow disabling colors

* Make  a public static variable

* Add documentation about disabling colors to readme

* Remove empty line

* Don't worry about missing styles if colors are disabled

* Short-circut the missing method the same way we do line function

* Rename Color's  variable to just  as we do camelcase here

* Check if NO_COLOR is set when writing to the terminal

* Add info about NO_COLOR environment variable to readme

---------

Co-authored-by: Jitendra Adhikari <2908547+adhocore@users.noreply.github.com>

README.md

@@ -508,6 +508,14 @@ Ahc\Cli\Output\Color::style('error', [
 ]);
 ```
 
+#### Disable colors
+
+```php
+Ahc\Cli\Output\Color::$enabled = false;
+```
+
+Colors will be automatically disabled if the `NO_COLOR` environment variable is set to true.
+
 ### Cursor
 
 Move cursor around, erase line up or down, clear screen.

src/Output/Color.php

@@ -50,6 +50,8 @@ class Color
     const GRAY     = 47;
     const DARKGRAY = 100;
 
+    public static bool $enabled = true;
+
     protected string $format = "\033[:mod:;:fg:;:bg:m:txt:\033[0m";
 
     /** @var array Custom styles */
@@ -138,6 +140,10 @@ public static function fg256(int $code): string
      */
     public function line(string $text, array $style = []): string
     {
+        if (!self::$enabled || getenv('NO_COLOR')) {
+            return $text;
+        }
+
         $style += ['bg' => null, 'fg' => static::WHITE, 'bold' => 0, 'mod' => null];
 
         $format = $style['bg'] === null
@@ -229,6 +235,10 @@ public function __call(string $name, array $arguments): string
         }
 
         if (!method_exists($this, $name)) {
+            if (!self::$enabled || getenv('NO_COLOR')) {
+                return $text;
+            }
+
             throw new InvalidArgumentException(sprintf('Style "%s" not defined', $name));
         }